Bath tub



FIG. 1 is a perspective view of a bath tub showing my new design;

FIG. 2 is a top plan view thereof;

FIG. 3 is a cross sectional view taken on line 3--3 of FIG. 2;

FIG. 4 is a cross sectional view taken on line 4--4 of FIG. 2; and

FIG. 5 is a cross sectional view taken on line 5--5 of FIG. 2. 

The ornamental design for a bath tub, as shown. 